Side wall tester



28, 1956 M. o. JOHNSTON SIDE WALL TESTER Filed Feb. 12, 1954 FEEQEA.

2 Sheets-Shea t l FEEL":

[Mm/70F Maw/c4 JOf/AASTO/V 147' TOP/Vf/5 1955 M. o. JOHNSTON 2,760,580

SIDE WALL TESTER Filed Feb. 12, 1954 2 Sheets-Sheet 2 a M i I, A 4 v v n 1 iAQNNL 7 ,1 .r w i w N T wfiqmfl 9 v. i 1 W9 5: a im/4 /A1 34 4 W H, 9 Wm 2| I.

E 2% aw wk 6 822 w W V Z FIE mz %'IOI SEE WALL TESTER Mordica (It. .iohnston, Glendale, Califi, assignor of onequarter to Madge Johnston, one-twelfth to Edgar C. .lohnston, J12, one-twelfth to Gordon C. Johnston, onetwelfth to Joseph Glenn Johnston, all of Longview, Tex., and one-eighth to Mordica 0. Johnston, JL, La ,olla, and one-eighth to Warren C. Johnston, Glendale,

alif.

Application February 12, 1954, Serial No. 409,878

10 Claims. (Cl. 166-120) This invention relates to a side wall testing tool and more particularly to a testing tool which may be set successively within the zones to be tested without removing the tool from the well between successive tests.

It is the principal object of this invention to provide a testing tool which may be set at any level within the well without the use of a tail pipe.

A further object of this invention is to provide a side wall testing tool which may be initially set by pumping fluid down within the test string and finally set by an upward pull on the test string.

A still further object of this invention is to provide a side wall testing tool wherein the hydrostatic pressures above and below the packedoil' zone are balanced.

Another object of this invention is to provide a side wall testing tool wherein circulation may be maintained in the well bore above the tool while the testing operation is being carried out.

Still another object of this invention is to provide a side wall testing tool wherein a test may be made either by using a pressure bailer or by direct flowing through the test string.

Various other objects of the invention will become apparent in reading the following detailed specification in conjunction with the drawings, in which:

Figs. 1:: and 1b are sectional views of the upper and lower portions, respectively, of a well tool embodying the principles of my invention, the parts being shown in the positions which they normally occupy when the tool is being lowered within the well.

Figs. 2a and 2b are similar sectional views of the upper and lower portions, respectively, of the tool shown in Figs. 1a and lb, showin the parts in the positions which they occupy when the tool is set within the well and while the fluid sample is being taken.

Fig. 3 is a sectional view taken on line 33 of Fig. 2b.

Fig. 4 is a sectional view taken on line 44 of Fig. In.

Fig. 5 is a sectional view taken on line 5-5 of Fig. la.

Fig. 6 is a sectional view of the lower end of a bailer used with the tool.

In general, it is customary when drilling a well to circulate drilling mud during the drilling operation. This drilling mud builds up a filter cake on the wall of the bore and seals any porous formations traversed thereby.

After the well is completed, it is customary to run a logging tool in the well to determine the various oil bearing horizons which the well traverses. When the oil bearing horizons have been located, some type of perforating tool is used to remove or penetrate the filter cake. It is then necessary to determine the flow characteristics of the difierent oil bearing zones and it is for this purpose that the tool herein described has been designed.

Now referring to the drawings, wherein similar reference numerals are used to designate the same parts throughout the various views, the numeral 10 generally indicates a tubular mandrel adapted to be connected to Patented Aug. 28, 1956 the lower end of a test string of tubing. As can be seen from an examination of the composite view shown in Figs. 1a and 1b, the mandrel 10 is comprised of a plurality of tubular elements 11 through 15, inclusive, threadedly connected together. A cap member in is threadedly secured to the lower end of the lowermost mandrel element 15. A lower abutment member 17 fixedly attached to the lower end of a rubber packing element 29 is connected to said cap portion 16 by a split ring 18 held together by bolts 1h. The upper end of the packing element 20 is fixedly attached to an abutment 21, which in turn is connected to a tubular spacin member 24 by a split ring 22 held together by the bolts 23. Another split ring 25 connects a second lower abutment 27 to the upper end of the spacing member 24, said split ring 25 being held together by means of bolts 26. Abutment member 27 is fixedly attached to the lower end of an upper packing element 25%, which turn has a second abutment member 29 fixedly attached to its upper end. A sleeve member 32 is connected to the abutment 29 by a split ring 30 held together by bolts 31.

All of these parts are slidable with relation to the mandrel with the exception of the cap member 16, whereby downward movement of the sleeve 32 with relation to the mandrel will cause the parts to telescope together, thus compressing the packing elements longitudinally and expanding them laterally outwardly into engagement with the walls of the well bore in the manner shown in Fig. 2b.

A plurality of upwardly extending dogs 33 are pivotally attached to the sleeve 32 by means of pivot pins 34. Each of said dogs 33 is provided with an inwardly extending lug 35 which engages the lower surface of a collar 36 slidably mounted on the mandrel 10. The collar 36 is urged downwardly by a spring 37 hearing against the upper end thereof, thus biasing the dogs 33 toward their retracted position in the manner shown in Fig. 1a. The upper end of the spring 37 bears against a downwardly facing internal shoulder on an annular piston 38 which slidably engages the mandrel element 13. The lower end of the piston engages a downwardly and inwardly tapered upper surface 33a on each of the dogs 33, whereby downward movement of the annular piston 38 will force the dogs 33 outwardly to the position shown in Fig. 2b, causing the dogs to engage and bite into the wall of the well bore.

Connected to the upper end of the sleeve 32 is a tubular sleeve extension member 39 slidably engaging the mandrel elements 11 and 12. The inner surface of the sleeve extension 39 has formed therein a plurality of longitudinally extending grooves or keyways 49 in a manner best seen in Fig. 5. Several keys l-l'are mounted on the mandrel section 12 and slidably engage the grooves 40 in the sleeve extension 3% to prevent relative rotation between the sleeve and the mandrel, but permit relative longitudinal movement therebetween. As can be seen in Fig. 5, there are eight keyways provided in the sleeve 39, but for reasons which will be explained later, there are only four keys 41 engaging alternate grooves. Adjacent its upper end, the sleeve 39 is milled out to the full depth of the grooves as indicated at 42. The milled portion of the sleeve 42 slidably engages an enlarged section 43 on the mandrel element ll when the sleeve isin its upper position relative to the mandrel.

Above the upper end of the sleeve extension member 39 the mandrel has an enlarged portion 99 forming a protective shoulder over the upper end of the sleeve 39 to prevent the upper end of the sleeve 39 from catching on the wall of the well bore and inadvertently actuating the packers while the tool is being withdrawn from the well. The shoulder 99 has a downwardly and outwardly sloping upper surface 100.

An inner mandrel, generally indicated at 44, comprising an upperportion45, an intermediate portion.46.and.

a lower portion 47, is slidably received within the outer mandrel 10. The upper portion 45 of the inner mandrel has a plurality of laterally extending bores. 49, each of which contains a locking ball 50 adaptedrto-seatwithin a groove 51 provided in the inner surface of an annulari plug 52 fastened within the section 12. of the outer mandrel 10. The lower portion of the inner upper. mandrel: section 45 is counterbored in the manner shown-at-48 and slidably receives a locking member 53 which abuts the inner surface of the balls 50 to retain the balls in the grooves 51. An annular spring retaining member 55 is threaded into the lower end of the upper mandrel section 45, and a compression spring 56 is confined between the upper surface of the spring retainer and a downwardly facing shoulder formed on the locking member 53,- thus urging the locking member 53 upwardly to its lock position. The intermediate portion 46 of the mandrel is threaded into the lower end of the spring retaining mem-.

face of the enlarged portion 57 of the mandrel and an internal shoulder 104 provided on the inner-surface of' the outer mandrel section 12.

As can best be seen in Fig. 2b, the spacing member 25 between the packers has a central portion ofenlarged internal diameter, forming an annular space 58 between thespacing member 24 and the outer surface of the mandrel 10. A plurality of lateral test ports 59 extend through said spacing member to provide fluid communication between the area of the well bore between the two packers and the annular chamber 58 between the mandrel and'thespacing member. The section 14 of the outermandrel has a plurality of test ports 60 extending through the walls thereof and so located as to be in register with the annular chamber 58 when the packers. are set within the well bore.

The inner mandrel 44 has a longitudinally extending central passageway 62. A solid section 61, adjacent the lower end of the inner mandrel, closes said central pas sage 62. A plurality of lateral test ports63 provide communication between the longitudinal passage 62 and the exterior of said mandrel. The test ports 63 are normally out of register with the ports 60. When the inner mandrel is unlocked and lowered with relation to the outer mandrel, the ports 63 are brought into register with the ports 60 in the manner shown in Fig. 2b. An O-ring' seal 64 is mounted on the inner mandrel above the test ports 63 and a similar O-ring seal 65 is mounted below the ports 63 to prevent fluid from passing between themandrels.

A plurality of equalizing ports 66 are located in the inner mandrel immediately below thesolid section 61', providing fluid communication between the exterior ofthe inner mandrel section and a longitudinalpassage 67 in the lower portion of mandrel 44. Passage 67 opens into the space below the inner mandrel. As can-beseerr in Fig. 1b, when the inner mandrel is in its-upper posi tion relative to the outer mandrel, the'ports 66'are-adapted to be in register with the port 60 in the section 14 of the outer mandrel 10, whereby fluid communication is provided between the area ofthe'well boreb'etweenthepackers and the interior of the outer tubular mandrel below the lower end of the inner mandrel.

Adjacent to and, below the enlarged'portion'43ithe outer,

mandrel 10 has a, plurality of lateralcirculation ports.69

extending there-through. Each ofv said ports 69'is in reg;

ister with one of the longitudinal grooves 40 in'the upper sleeve extension 39. The grooves which are in register with the lateral ports 69 are the grooves in which the keys 41 are omitted, whereby fluid pumped down through the test string may flow out through the lateral ports 69, down through the grooves 40, through the grooves 97 provided in the outer surface of the lower portion of the mandrel section 12, into anannular space 98 above the piston'38i Some of the fluid pumped down will pass through restricted ports 70 in the lower end of the mandrel section 12 into the annular passageway 71 between the inner and outer mandrels. However, due to the restricted size ofthe ports 70, suificient pressure will be built up in the annular chamber 98 to force the piston 38 down and actuate the dogs 33.

After the tool has been set in the well, the upper end of the sleeve extension member 39 is no longer in sliding engagement with the enlarged portion 43 of the mandrel. Thus, fluid communication is established from the area of the bore above the packers through the longitudinal grooves 40 in the sleeve extension 39, the grooves 97 in the mandrel, the ports 70, the passageway 71 between the mandrels, longitudinal passageways 72 provided in the section 14 of the outer mandrel, and the longitudinal passageway 73 to the area of the bore below the packers to hydrostatically balance the tool.

An internalsleeve 101 is fastened within the lower portion of the mandrel section 11. The upper end of said sleeve 101 is upwardly and outwardly tapered in themanner shown at 102. The sleeve slidably guides a bailer generally indicated at 74 into fluid-tight engagement with the upper end of the inner mandrel 44.

As best shown in Fig. 6, the bailer, generally indicated at 74, comprises a body portion 75 which is closed at its upper end- (not shown). A reduced internal diameter portion 76 is provided adjacent the lower end of the body 75. Threadedly received within the reduced diameterportion 76 is a tubular extension member 77 having an upwardly facing valve seat 78 formed on its upper end. A valve 79, adapted to cooperate with the seat 78, is mounted within the bailer and has a valve stem 80 attached theretoby a cap screw 81. The valve stem 80- extends downwardly within but spaced from the tubular extension-77. The lower end of the valve stem 80 is enlarged; as shown at 82, and is in sliding engagement withthe inner surface of the bailer extension. The lower enlarged portion 82 has an internal longitudinal passageway 83 formed therein which is connected with the annular'space surrounding the upper portion 88 by a plurality ofdiagonal ports 84. An external annular groove 87, formed in the outer surface of the lower valve stem portion 82 adjacent the upper end thereof, is adapted to receive a plurality of locking balls 86 mounted in bores- 85 through the walls of the bailer extension 77. A locking sleeve 88' is slidably mounted on the external surface of the bailerextension 77 and is adapted to force the balls 86 inwardly into engagement with the annular groove 87 to prevent relating longitudinal movement between the valve stem and the bailer extension. The sleever 88 has a portion of'enlarged internal diameter 89 adjacent its lower end.

When the sleeve is raised relative to the bailer extension 77, the-balls 86'are permitted to enter said enlarged wardly facing external shoulder 94 on the lower portion.

The downward movement of the 82 of the valve stem to limit the downward movement of the valve stem relative to the extension 77. The lower end 82 of the valve stem extends below the end of the tubular extension 77 and has a spring retaining member 95 fastened to its lower end. A spring 96, confined between the upper surface of the spring retainer 95 and the lower surface of the bailer extension, normally urges the valve stem downwardly, thereby urging the valve 79 into seating engagement with the valve seat 78.

The device is operated in the following manner: After the oil bearing horizons have been located by means of a logging device and the filter cake removed or perforated in the manner described above, the device is lowered into the well on the lower end of a test string of tubing. When the device is adjacent the horizon to be tested, fluid is pumped down within the well string and passes out ports 69 into the longitudinal grooves 40 in the upper sleeve extension 39. The fluid passes downwardly through the grooves 40 and the grooves 97 into the annular chamber 93 and applies pressure to the upper surface of the piston 38, forcing the piston downward and thus pivoting the dogs 33 outwardly into engagement with the bore wall. A rise in the pressure of the fluid being pumped will indicate when the dogs 33 are properly extended.

After the dogs have been expanded into engagement with the bore wall, an upward pull is applied to the test string, thus pulling the mandrel 1t upwardly relative to the sleeve 32. The relative movement between the mandrel lb and sleeve 32 forces the packing elements 2% and 28 to be longitudinally compressed and hence laterally expanded into engagement with the bore wall in the manner shown in Fig. 26. The upward movement of the mandrel also moves the ports 60 from the position shown in Fig. lb to the position shown in Fig. 21), wherein they are adjacent the enlarged chamber 58 provided on the interior of the spacing member 2 After the tool has been properly set, a pressure bailer 74- is lowered within the test string by means of a wire line (not shown) until the tubular extension 77 on the lower end thereof is slidably received within the upper portion 45 of the inner mandrel.

The inner mandrel has an O-ring seal 105 on its inner surface to prevent loss of fluid between the inner surface of the mandrel and the bailer extension 77. When the bailer extension 77 enters the upper end of the mandrel, the lower end of the valve stem 82 abuts the end of the lock member 53 and forces said member downwardly-to release the ball lock between the inner and outer mandrels. Subsequent to the unlocking of the mandrels, the upper end of the inner mandrel abuts the lower end of the locking sleeve 38 and forces said sleeve upwardly relative to the bailer extension 77 thus releasing the ball lock between the bailer extension 77 and the valve stem 80 and permitting the valve 79 to open and allow fluids to pass into the bailer 74.

When the inner mandrel is unlocked from the outer mandrel, the weight of the bailer 74 moves said mandrel downwardly relative to the outer mandrel, to bring the ports 63 into register with the ports 60, thereby permitting the fluid from the test zone to flow into the inner mandrel and upwardly therethrough into the bailer.

After the test has been completed, the bailer 74 is removed by means of the wire line and drawn to the surface for examination of the contents contained therein. When the bailer is removed from the inner mandrel, the spring 96 forces the valve stem downwardly to close the valve 79 against the seat 78. Thus the sample is maintained at the same pressure at which it is collected. When the valve stem moves down, the groove 87 is again brought into register with the balls 86 and the spring 99 forces the sleeve 88 downwardly to force the balls 86 into the groove 87 and lock the valve in closed relation. Similarly, the spring 1433 forces the inner mandrel upwardly relative to the outer mandrel until the balls 50 are again opposite the groove 51 in the plug 52, and the spring 56 forces the lock member 53 upwardly, forcing the balls outwardly into the groove 51 to lock the inner mandrel in its upper position.

In order to make a flow test by having the test fluid flow upwardly within the test spring, a dummy bailer open at its upper end may be lowered within the test string to actuate the inner mandrel and bring the test ports therein into register with the test ports in the outer mandrel.

While I have shown the preferred form of my invention, it is to be understood that various changes may be made in its construction by those skilled in the art without departing from the spirit of the invention as defined in the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

l. A side wall tester adapted to be connected to the lower end of a test string of tubing comprising an outer tubular mandrel, upper and lower packers mounted on said mandrel and spaced from each other, means for setting said packers in a well bore, test ports in said outer mandrel providing communication between the portion of the well bore between said packers and the interior of said mandrel, an inner tubular mandrel mounted for limited longitudinal movement within said outer mandrel, the central passage through said inner mandrel being closed adjacent its lower end, test ports in said inner mandrel immediately above the closed portion thereof adapted to be brought into register with the ports in said outer mandrel, a bailer adapted to be lowered on a wire line within the test string of tubing, and means on said bailer for moving said inner mandrel longitudinally within said outer mandrel to bring said inner and outer mandrel test ports into register.

2. A side wall tester comprising an outer tubular mandrel adapted to be connected to the lower end of a test string of tubing, upper and lower packers mounted on said mandrel and spaced from each other, means for setting said packers in a well bore, test ports in said outer mandrel providing communication between the portion of the well bore between said packers and the interior of said mandrel, an inner tubular mandrel mounted for limited longitudinal movement within said outer mandrel, the central passage through said inner mandrel being closed adjacent its lower end, means urging said inner mandrel toward its upper position, test ports in said inner mandrel immediately above the closed portion thereof adapted to be in register with the ports in said outer mandrel when said inner mandrel is in its lower position, a bailer defining a fluid-receiving chamber valve at its lower end, a tubular extension slidably received in the lower end of said bailer and adapted to be slidably received within the upper end of said inner mandrel, said tubular extension being attached to said valve, means urging said extension downwardly relative to said bailer to urge said valve toward its closed position, abutment means in said inner mandrel, whereby when said bailer is lowered the tubular extension will slide into the upper end of said inner mandrel and the lower end will abut said abutment means first moving said inner mandrel down relative to said outer mandrel to bring said ports into register and upon further downward movement of said bailer opening the valve in the bailer to allow fluid to enter therein, and whereby when said bailer is removed first the bailer valve will close and then the ports in the inner mandrel will move out of register with the ports in said outer mandrel.

3. A side wall tester comprising an outer tubular mandrel adapted to be connected to the lower end of a test string of tubing, upper and lower packers mounted on said mandrel, the lower end of the lower packer being fixed to the lower end of said mandrel, a tubular spacing member slidably mounted on said mandrel and connected to the lower end of the upper packer and the upper end of the lower packer, a plurality of wall engaging dogs pivotally connected to the upper end of said upper packer and extending upwardly therefrom, means responsive to hydraulic pressure within the test string for pivoting said Well engaging members outwardly into engagement with the bore wall, whereby subsequent upward movement of said mandrel will telescope said packers on said mandrel and expand them laterally outward into engagement with the bore wall, lateral test ports in said tubular spacing member, lateral test ports in said mandrel adapted to register with the ports in said spacer member when the packers are set in the bore, an inner {obi-tar mandrel mounted for limited longitudinal movement within said outer mandrel, the central passage through said inner mandrel being closed adjacent its lower end, test ports in said inner mandrel immediately above the closed portion thereof adapted to be brought into register with the ports in the outer mandrel by relative movement between said mandrels, and means for causing said relative movement.

4. A side wall tester comprising an outer tubular mandrel adapted to be connected to the lower end of a test string of tubing, upper and lower packers mounted on said mandrel, the lower end of the lower packer being fixed to the lower end of said mandrel, a tubular spacing member slidably mounted on said mandrel and connected to the lower end of the upper packer and the upper end of the lower packer, a plurality of wall engaging dogs pivotally connected to the upper end of said upper packer and extending upwardly therefrom, said dogs having downwardly and inwardly tapered inner surfaces, a tubular sleeve fixed to and extending upwardly from the upper end of said upper packer and slidable on said mandrel, longitudinally extending grooves in the inner surface of said sleeve, means on said mandrel closing the upper end of the grooves when the sleeve is in its upper position relative to said mandrel, an annular piston slidably mounted between said sleeve and mandrel adjacent the lower end of the sleeve and engaging the inner surfaces of said dogs, ports in said mandrel providing communication between the interior of said mandrel and said grooves above said piston, whereby fluid pumped down said test string will apply pressure to said piston and force said dogsoutwardly into engagement with the bore wall and subsequent upward movement of said mandrel will telescope said packers on said mandrel and expand them laterally into engagement with the bore wall.

5. A side wall tester comprising an outer tubular mandrel adapted to be connected to the lower end of a test string of tubing, upper and lower packers mounted on said mandrel, the lower end of the lower packer being fixed to the lower end of said mandrel, a tubular spacing member slidablyimounted on said mandrel and connected to the lower end ofv the upper packer and the upper end of the lower packer, a plurality of wall engaging dogs pivotally connected to the upper end of said upper packer and. extending upwardly therefrom, said dogs having downwardly and inwardly tapered inner surfaces, a tubular sleeve fixed to and extending upwardly from the upper end of said upper-packer, and slidable on said mandrel, longitudinally extending grooves in the inner surface of said sleeve, means on said mandrel closing the upper end of the grooves when the sleeve is in its upper position relative to said mandrel, an annular piston slidably mounted between said sleeve and mandrel adiacent the lower end of the sleeve andengaging the inner surfaces of said dogs, ports in said mandrel providing communication between the interior of said mandrel and said grooves above said piston, whereby fluid pumped down said test string will apply pressure to said piston and force said dogs outwardly into engagement with the bore wall. and subsequent upward movement of asid mandrel will telescope said packers on said mandrel and expand them laterally into engagement with the bore wall, lateral test ports in said tubular spacingmember, and lateral test ports-in said mandreladapted to register with the ports in said spacer member when the packers are set in mandrel adapted to be connected to the lower end of a test string of tubing, upper and lower packers mounted on said mandrel, the lower end of the lower packer being fixed to the lower end of said mandrel, a tubular spacing member slidably mounted on said mandrel and connected to the lower end of the upper packer and the upper end of the lower-packer, a plurality of wall engaging dogs pivotally connected to the upper end of said upper packer and extending upwardly therefrom, said dogs having downwardly and inwardly tapered inner surfaces, a tubular sleeve fixed to and extending upwardly from the upper end of said upper packer and slidable on said mandrel, longitudinally extending grooves in the inner surface of said sleeve, means on said mandrel closing the upper end of the grooves when the sleeve is in its upper position relative to said mandrel, an annular piston slidably mounted between said sleeve and mandrel adjacent the lower end of the sleeve and engaging the inner surfaces of said dogs, ports in said mandrel providing communication between the interior of said mandrel and said grooves above said piston, whereby fluid pumped down said test string will apply pressure to said piston and force said dogs outwardly into engagement with the bore wall andsubsequent outward movement of said mandrel will telescope said packers on said mandrel and expand them laterally into engagement with the bore wall, lateral test ports in said tubular spacing member, lateral test ports in said mandrel adapted to register with the ports in said spacer member when the packers are set in the bore, an inner tubular mandrel mounted for limited longitudinal movement within said outer mandrel, the central passage through said inner mandrel being closed adjacent its lower end, test ports in said inner mandrel immediately above the closed portion thereof adapted to be brought into register with the ports in the outer mandrel .by relative movement between said mandrels, and means for causing said relative movement.

7. A side wall tester comprising an outer tubular mandrel adapted to be connected to the lower end of a test string'of tubing, upper and lower packers mounted on said mandrel and spaced from each other, means for setting said packers in a well bore, test ports in said outer mandrel providing communication between the portion of the well bore between said packers and the interior of said mandrel, an inner tubular mandrel mounted for limited longitudinal movement within said outer mandrel, the central passage through said inner mandrel being closed adjacent its lower end, means urging said inner mandrel toward its upper position, test ports .in said inner mandrel immediately above the closed portion thereof adapted to be in register with the ports in said outer mandrel when said inner mandrel is in its lower position, a bailer defining a fluid-receiving chamber having a valve at its lower end, a tubular extension slidably received in the lower end of said bailer and adapted to be, slidably received within the upper end of said inner mandrel, said tubular extension being attached to said valve, means urging said extension downwardly relative to said bailer to urge said valve toward its closed position, abutment means in said inner mandrel, whereby when said bailer is lowered the tubular extension will slideinto the upper end of said inner mandrel and the lower end will abut said abutment means first moving said inner mandrel down relative to said outer mandrel to bring said ports into register and upon further downward movement of said bailer opening the valve in the bailer to allow fluid to enter therein, and whereby when said bailer is removed first the bailer valve will close and then the ports in the inner mandrel will move out of register with-the ports in said outer mandrel, and means for bypassing fluid from below the lower packer to above the upper packer.

8. A side wall tester comprising an outer tubular mandrel adapted to be connected to the lower end of a test string of tubing, upper and lower packers mounted on said mandrel, the lower end of the lower packer being fixed to the lower end of said mandrel, a tubular spacing member slidably mounted on said mandrel and connected to the lower end of the upper packer and the upper end of the lower packer, a plurality of wall engaging dogs pivotally connected to the upper end of said upper packer and extending upwardly therefrom, means responsive to hydraulic pressure within the test string for pivoting said well engaging members outwardly into engagement with the bore wall, whereby subsequent upward movement of said mandrel will telescope said packers on said mandrel and expand them laterally outward into engagement with the bore wall, lateral test ports in said tubular spacing member, lateral test ports in said mandrel adapted to register with the ports in said spacer member when the packers are set in the bore, an inner tubular mandrel mounted for limited longitudinal movement within said outer mandrel, the central passage through said inner mandrel being closed adjacent its lower end, test ports in said inner mandrel immediately above the closed portion thereof adapted to be brought into register with the ports in the outer mandrel by relative movement between said mandrels, means for causing said relative movement, and means for bypassing fluid from below the lower packer to above the upper packer.

9. A side wall tester comprising an outer tubular mandrel adapted to be connected to the lower end of a test string of tubing, upper and lower packers mounted on said mandrel, the lower end of the lower packer being fixed to the lower end of said mandrel, a tubular spacing member slidably mounted on said mandrel and connected to the lower end of the upper packer and the upper end of the lower packer, a plurality of wall engaging dogs pivotally connected to the upper end of said upper packer and extending upwardly therefrom, said dogs having downwardly and inwardly tapered inner surfaces, a tubular sleeve fixed to and extending upwardly from the upper end of said upper packer and slidable on said mandrel, longitudinally extending grooves in the inner surface of said sleeve, means on said mandrel closing the upper end of the grooves when the sleeve is in its upper position relative to said mandrel, an annular piston slidably mounted between said sleeve and mandrel adjacent the lower end of the sleeve and engaging the inner surfaces of said dogs, ports in said mandrel providing communication between the inerior of said mandrel and said grooves above said piston, whereby fluid pumped down said test string will apply pressure to said piston and force said dogs outward into engagement with the bore wall and subsequent upward movement of said mandrel will telescope said packers on said mandrel and expand them laterally into engagement with the bore wall, lateral test ports in said tubular spacing member, lateral test ports in said mandrel adapted to register with the ports in said spacer member when the packers are set in the bore, an inner tubular mandrel mounted for limited longitudinal movement within said outer mandrel, the central passage through said inner mandrel being closed adjacent its lower end, test ports in said inner mandrel immediately above the closed portion thereof adapted to be brought into register with the ports in the outer mandrel by relative movement between said mandrel, means for causing said relative movement, and means for bypassing fluid from below the lower packer to above the upper packer.

10. A side wall tester adapted to be connected to the lower end of a test spring of tubing comprising an outer tubular mandrel, upper and lower packers mounted on said outer mandrel and spaced from each other, means for setting said packers in a well bore, said outer mandrel having test ports providing communication between the portion of the well bore between said packers and the interior of said outer mandrel, an inner tubular mandrel mounted for limited longitudinal movement within said outer mandrel, the central passage through said inner mandrel being closed adjacent its lower end, said inner mandrel having test ports providing communication between the exterior of said inner mandrel and the central passage thereof, said inner mandrel test ports being adapted to be brought into register with the test ports in said outer mandrel, means normally urging said inner mandrel to a first position within and relative to said outer mandrel whereby the inner and outer mandrel test ports are out of register, and means adapted to be lowered through the test string of tubing to move the inner mandrel to a second position relative to said outer mandrel whereby said inner and outer test ports are in register.

References Cited in the file of this patent UNITED STATES PATENTS 2,050,970 Hughes Aug. 11, 1936 2,107,655 Vogt et al. Feb. 8, 1938 2,227,731 Lynes Jan. 7, 1941 2,328,840 OLeary Sept. 7, 1943 2,404,825 Brown et al July 30, 1946 2,675,876 Conrad et a1 Apr. 20, 1954 

